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Two closely related alien submerged aquatic plants were introduced into Europe. The new invader (Elodea nuttallii) gradually displaced E. canadensis even at sites where the latter was well established. The aim of the study was to evaluate the combined effects of environmental factors on several phenotypic characteristics of the two Elodea species, and to relate these phenotypic characteristics to the invasion success of E. nuttallii over E. canadensis.In a factorial design, Elodea plants were grown in aquaria containing five different nitrogen concentrations and incubated at five different light intensities. We used six functional traits (apical shoot RGR), total shoot RGR, relative elongation, root length, lateral spread, branching degree) to measure the environmental response of the species. We calculated plasticity indices to express the phenotypic differences between species.Light and nitrogen jointly triggered the development of phenotypic characteristics that make E. nuttallii a more successful invader in eutrophic waters than E. canadensis. The stronger invader showed a wider range of phenotypic plasticity. The apical elongation was the main difference between the two species, with E. nuttallii being more than two times longer than E. canadensis. E. canadensis formed dense side shoots even under high shade and low nitrogen levels, whereas E. nuttallii required higher light and nitrogen levels.We found that under more eutrophic conditions, E. nuttallii reach the water surface sooner than E. canadensis and through intensive branching outcompetes all other plants including E. canadensis. Our findings support the theory that more successful invaders have wider phenotypic plasticity. [ABSTRACT FROM AUTHOR]

We studied the kinetics of solid state dewetting of a thin Mo film deposited on a sapphire substrate. The overall kinetics of the process can be described by the Johnson-Mehl-Avrami-Kolmogorov equation with two different exponents, indicating a decrease of the holes nucleation rate for the long annealing times. We related this decrease to the role of grain boundaries and triple junctions in the nucleation of holes, and the grain growth in the film during annealing. Every expanding hole was partially surrounded by the elevated, abnormally large grains, while the remaining part of the hole contacted an unperturbed film of the original thickness. The expansion of the holes occurred predominantly in the direction of the flat film. We formulated a kinetic model of hole expansion based on surface diffusion along the edge of a flat rim in the direction of an abnormal elevated grain. [ABSTRACT FROM AUTHOR]

Abstract: The present paper introduces the results of a spatial-economic analysis that identifies the least cost rural electrification options that can bring the persistent energy poverty to an end in Sub Saharan Africa. The rationale behind the analysis is that the applicable energy technologies have gone through fundamental changes and these have profound effects on the competitiveness of the various options. The least cost distributed generation options are calculated for each geographical location for mini hydro, off grid PV and diesel generators options and it is compared to the electricity grid extension. The methodology presented in this manuscript organises the scarcely available energy-related local and regional geo-information into comprehensible maps. The set of tools presented and the results based on those analyses can support decision and policy makers to plan for the least-cost rural electrification options while also adapting to the most effective way to reduce energy poverty. This can help in the national rural electrification plans by delineating which communities cannot be reached by existing grid without excessive extension costs and gives the alternative distributed generation option. [Copyright &y& Elsevier]

If a finite abelian group is factored into a direct product of its cyclic subsets, then at least one of the factors is periodic. This is a famous result of G. Hajós. We propose to replace the cyclicity of the factors by an abstract property that still guarantees that one of the factors is periodic. Then we present applications of this approach. [ABSTRACT FROM AUTHOR]

The paper deals with m by n rectangular arrays whose mn cells are filled with symbols. A section of the array consists of m cells, one from each row and no two from the same column. The paper focuses on the existence of sections that do contain symbols with high multiplicity. [ABSTRACT FROM AUTHOR]

Abstract: Corrosion behaviour of pure aluminium galvanically connected to metallic copper or in the presence of Cu2+ ions was investigated by electrochemical measurements in Na2SO4 and Na2SO4 +NaCl test solutions. It has been found that in aerated Cl− ion containing solutions pitting corrosion of aluminium emerged immediately, while in the absence of oxygen this process was less violent. Effect of passivating pre-treatment of aluminium surface on corrosion behaviour Cu–Al bimetallic system is also demonstrated. [Copyright &y& Elsevier]

Electrosorption of rhodium on a polycrystalline platinum surface has been studied. It has been found that a complete Rh-coverage can be obtained by spontaneous adsorption via the ionization of preadsorbed hydrogen. Underpotential deposition of rhodium has been observed both in 0.5 M H2SO4 and 0.2 M HCl supporting electrolytes. The value of the underpotential shift was found to be about 100–120 mV. [Copyright &y& Elsevier]

A simple redox titration method has been developed for the measurement of the Pd content and dispersity of palladium catalysts. First, the sorbed hydrogen content, then the Pd content and finally, the amount of adsorbed oxygen must be measured and from these data the dispersity can be easily calculated. [Copyright &y& Elsevier]

The adsorption of cinchonidine (CD) on polycrystalline platinum surfaces in 0.5 mol dm−3 H2SO4 has been investigated. It has been found that adsorption is irreversible, desorption takes place at relatively high potentials simultaneously with the oxidation of CD molecules. According to our results CD covers only a part of the Pt surface and maximal coverage is influenced by the surface structure. Some assumptions for the site requirement of an adsorbed CD molecule have also been made. [Copyright &y& Elsevier]

A magnetically disordered state was experimentally identified in bulk nanocrystalline iron at low temperatures. The structure and purity of as-milled samples (one milled in a helium atmosphere and the other in vacuum) were checked by X-ray diffraction and transmission electron microscopy methods. Low-field and high-field hysteresis loops at different temperatures as well as field-cooled and zero-field-cooled magnetization measurements at different external magnetic fields are presented. Frozen magnetic states were observed in both samples. It appears that ball-milled iron behaves much like a two component system with a ferromagnetic and a spin-glass-like phase. [ABSTRACT FROM AUTHOR]

Wittmeyer's pseudoinverse iterative algorithm is formulated as a dynamic connectionist Data Compression and Reconstruction (DCR) network, and subnets of this type are supplemented by the winner-take-all paradigm. The winner is selected upon the goodness-of fit of the input reconstruction. The network can be characterised as a competitive-cooperative-competitive architecture by virtue of the contrast enhancing properties of the pseudoinverse subnets. The network is capable of fast learning. The adopted learning method gives rise to increased sampling in the vicinity of dubious boundary regions that resembles the phenomenon of categorical perception. The generalising abilities of the scheme allow one to utilise single bit connection strengths. The network is robust against input noise and contrast levels, shows little sensitivity to imprecise connection strengths, and is promising for mixed VLSI implementation with on-chip learning properties. The features of the DCR network are demonstrated on the NIST database of handprinted characters. [ABSTRACT FROM AUTHOR]

In our study, we report on the adult population's nutritional status and diet related results of the E-Harmony prevention programme begun in 2014. Local population intervention programs that focus on moderating overweight, obesity, and the abdominal obesity and healthy diet are still needed. [Extracted from the article]

Jerky character of austenite/martensite transformation has been investigated in NiFeGaCo shape memory single crystalline samples simultaneously by Differential Scanning Calorimeter, DSC, and by Acoustic-Emission, AE. Statistical analysis of the noise signals resulted in the same energy exponents, ε , about 1.7 ± 0.1 for heating, as well as 2.0 ± 0.1 for cooling, from both acoustic emission and thermal signals at low cooling rates (dT/dt = 0.1 K/min). The exponents of peak amplitudes of AE signals are α = 2.5 ± 0.1 and 2.9 ± 0.1 for heating and cooling, respectively. The obtained exponents fulfill the scaling rule ( α −1)/( ε −1) = z with z = 2. Optical observation of the transformation confirmed that it takes place by single interface motion, i.e. the jerky character is the result of the stop-and-go type motion of this interface. [ABSTRACT FROM AUTHOR]

The paper introduces a transparent methodology to assess new suitable locations for mini and small hydro power plants in Europe. The expansion of hydro electricity production is a policy focus not only in Europe, but in the US (Hydropower Regulatory Efficiency Act of 2013) and in the developing world as well. The analysis of the technical potential points out the exact geographical locations and their corresponding capacities instead of only a theoretical potential; therefore it can serve as a reference for the policy debate over the sustainable management of water resources. This debate is reflected already in two major European policies: the Water Framework Directive (WFD) (2000/60/EC) and the RES Directive (2009/28/EC) on the promotion of the use of energy from renewable sources. As both policies have major influence on the priorities of water use, it is important to identify water management practices capable of accommodating sustainable energy purposes while maintaining water quality objectives at the same time. As the WFD poses limitation on the further expansion of large scale hydro options in the European water bodies, the present study focuses on local mini and small hydropower options and their suitability mapping. The presented, geographically explicit method is based on geospatial analysis and the results can contribute to the prioritization of potential hydro power sites in order to improve water quality and its use for energy simultaneously. [ABSTRACT FROM AUTHOR]

Unsupported and SiO2 supported GePt bimetallic catalysts were prepared by depositing Ge on to Pt underpotentially. Surface-sensitive cyclic voltammetry of Pt black indicated that Ge covered ca. 40–45% of the Pt surface, whereas XPS showed just ∼96% Pt and ∼4% Ge (normalized to ). High-resolution Ge map of GePt black obtained by Energy Filtered TEM (EFTEM) showed Ge scattered in the near-surface regions. Both catalysts were tested in hexane (nH) transformation reactions between 543 and 603 K and 60 to 480 Torr H2 pressure (with 10 Torr nH), and compared with the parent Pt catalysts. GePt/SiO2 catalyst was also tested with methylcyclopentane (MCP). Adding Ge to Pt/SiO2 lowered the activity; the opposite effect was observed with GePt black. The selectivities of saturated products on bimetallic catalysts decreased, while those of hydrogenolysis products, benzene and hexenes increased in nH transformations over supported catalyst. The reverse effects were observed over the black samples where addition of Ge prevented accumulation of adventitious carbon. Ring opening was the main reaction with MCP, together with some fragments, benzene and unsaturated hydrocarbons. Ring opening of MCP became more selective with decreasing temperature and increasing hydrogen pressure. Ge on GePt black blocked contiguous Pt sites favoring the formation of coke precursors. The different catalytic behavior of GePt/SiO2 indicated somewhat different Pt–Ge interaction(s). [Copyright &y& Elsevier]

Abstract: Fly ash samples of cement works were analysed using slurry nebulization inductively coupled plasma atomic emission spectrometric (ICP-AES). Because of the influence of the experimental factors on the signal intensity, the optimal conditions of the analysis circumstances were determined. Control analyses (wet digestion followed by ICP-AES, and XRF of dry powders (pressed pellets)) were also carried out to compare the results. Based on the result, it was concluded that the slurry nebulization method using slurry standard of same type reference material for calibration can be applied for rapid but less precise (RSD 5–10%) determination of the elements in fly ash. [Copyright &y& Elsevier]

A Cu–24.0 at.% Al–2.2 at.% Ni–0.5 at.% B shape memory alloy was investigated experimentally under uniaxial tensile stress (σ) up to 10 MPa. Transformation temperatures and transformation strains as a function of σ were evaluated from the simultaneously measured temperature–elongation and temperature–resistance curves. Using appropriate analysis [Philos. Mag. B 82 (2002) 105; Scripta Mater. 43 (2000) 691; J. Phys. IV 11 (2001) Pr8], it is possible to determine the stress dependence of the volume derivatives of the elastic and dissipative free energies at the start and finish points of the forward and reverse transformations from the measured transformation temperatures and strains. From our experimental data, the above volume derivatives were calculated as a function of stress. The dissipative contributions both of the forward and reverse transformations increase with increasing stress. In case of elastic contributions, the difference between the forward and reverse transformation values as well as their decreasing tendency with increasing stress was clearly proved. [Copyright &y& Elsevier]

Substitution of Nickel by Sulfur leads to bulk metallic glass formation in eutectic Ti75Ni25. In order to understand the improved glass forming ability, a detailed analysis of the melt dynamics was performed. We measured the density, the viscosity, and the self-diffusion of Ti75Ni25−xSx (x = 0, 5, 8) melts as a function of temperature. Moreover, the viscosity was measured under reduced gravity conditions to benchmark ground-based data. The self-diffusion coefficients were probed by incoherent, quasi-elastic neutron scattering. All measurements were combined with electrostatic or electromagnetic levitation, in order to process these highly reactive Titanium-based melts. From the measured density, the packing fraction was calculated as a function of temperature. In contrast to other bulk metallic glasses, the decrease in melt dynamics comes along with the decrease in packing density. [ABSTRACT FROM AUTHOR]

The absence of publicly available up-to-date costs breakdown data on photovoltaic (PV)/hybrid mini-grids in Sub-Saharan Africa (SSA) is a barrier that needs to be resolved in order to overcome challenges in rural electrification planning, regulation, life-cycle operation, financing, and funding. The primary aim of this research is to provide better understanding of the cost structures of PV/hybrid mini-grid projects in Sub-Saharan Africa. The review on existing literature reveals significant lack of transparency and inconsistencies in PV/hybrid mini-grid costs. This paper aims to support the fact that there still remains a strong need to reduce the gap between current business model concepts and successfully implemented scale-up electrification models. Based on the experience of PV/hybrid mini-grids projects implemented in various rural communities of SSA, we propose a multi-dimensional cost analysis with a standardised break-down of the real costs of installed projects. Subsequently, we assess the main social and environmental implications and we identify barriers that appear to hinder successful PV mini-grid planning and subsequent implementation in SSA. Africa has the unique opportunity to utilize renewable energy as a primary energy source. Indeed, the continent has the potential to bring electricity especially to its rural population by means of PV/hybrid mini-grids. However, the capability of public and private sector investors to pre-evaluate projects is limited by the lack of locally available information on PV/hybrid mini-grid costs or the reliability of data (when available). Multi-dimensional cost analysis of social and environmental impacts from this study highlight that PV/hybrid mini-grids offer a unique opportunity to create a standardised framework for quantifying costs of PV/hybrid mini-grids in SSA, that can support decision-making processes for designing viable business models. Findings show that there is a strong need to minimise the data quality gap between current business model and that of successfully implemented PV/hybrid mini-grids electrification projects. This gap could be mitigated through studying the issues that influence mini-grid costs (both hardware and software). In addition to understanding other factors that can influence project costs such as the market maturity and remoteness of the site, organisation capability, development approach, and level of community involvement. Regarding policy considerations, stronger political will coupled with proactive rural electrification strategies and targeted renewable energy regulatory framework would be essential in order to establish viable dynamic domestic market for off grid renewables. In the presented benchmarking analysis, the experiences of public and private development organisations are synchronized to contribute to the furthest extent possible to facilitate the assessment. Those include the disaggregation of component costs according to their unit in order to make comparison more accurate and include site-specific parameters in the discussion of costs. [ABSTRACT FROM AUTHOR]

Following the successful Feed-in Tariffs (FiTs) system worldwide, few countries have implemented FiTs explicitly tailored for off-grid or mini-grid systems. This study takes an integrated approach to examine the feasibility of an off-grid Feed-in Tariff (off-FiT) for existing and new remote mini-grids in Tanzania, using a combination of geographical analysis, technical, economic and institutional assessments. Based on detailed modelling of two community off-grid cases, (i) PV-diesel and (ii) mini-hydro, we identify least-cost rural electrification options that make solar and mini-hydro energy competitive with diesel generators and potential effect of the support scheme on rural electrification plans. In the first case, we illustrate where the off-FiT complements diesel generation of an existing mini-grid (PV-diesel). In the second case (mini-hydro), we illustrate conditions where the off-FiT policy brings mini-hydro generation to non-electrified communities and sells renewable electricity directly to new customers. Currently, Tanzania has Standardized Power Purchase (SPP) rates, which target generators connected to the national grid and distribution systems of mini-grids or isolated grids. We found for the off-FiT tariff the total amount needed to support the same number of customers by solar and hydro-mini grids versus diesel would be of 31.5 million US$, or a premium of 0.11 US$/kWh to the present current SPPs tariff of 0.24 US$/kWh for PV. We also found that a technology specific FiT tariff would be most suitable to attract national and international investors by providing a rate of return that compensates the risk of the investment. The overall support is comparable to the 36 million US$ that the government currently subsidizes and allocates to diesel mini-grids in country, and this shows the potential for a long-term renewable energy strategy for mini-grid areas. [ABSTRACT FROM AUTHOR]

Abstract: Rh was deposited on a parent platinum black catalyst by an underpotential deposition method. Mean particle size and bulk composition of this Rh–Pt sample was determined by TEM and EDS. No individual Rh grains could be observed, but Rh was present in the near-surface regions, according to energy-filtered TEM images. The surface-sensitive cyclic voltammetry indicated 15–20% Rh on the surface. XPS, in turn, detected ∼2–2.5% Rh in the information depth. The Rh–Pt catalyst was tested in methylcyclopentane hydrogenative ring-opening reaction between 468 and 603 K and 8 to 64 kPa H2 pressure (with 1.3 kPa MCP). The parent Pt black as well as a Rh black catalyst was also studied for comparison. MCP produced ring opening and hydrogenolysis products. The ring-opening products (ROP) consisted of 2- and 3-methylpentane (2MP and 3MP) as well as hexane (nH). These were the main products, together with some fragments and unsaturated hydrocarbons. The amount of the latter class increased at higher temperatures. The selectivities of ROP, fragments, and benzene over Rh–Pt catalyst as a function of temperature were between the values observed on Pt and Rh. The hydrogen pressure dependence of selectivities on Rh–Pt was more similar to that observed on Pt. Four subsequent treatments with O2 and H2 up to were applied on the bimetallic catalyst, followed by XPS and catalytic runs, respectively. These treatments promoted structural rearrangement, with XPS detecting less Rh in the near-surface region, partly as oxidized Rh after O2 treatment. The catalytic behavior became more Pt-like on these structural and composition changes. We concluded that adding a relatively small amount of Rh to Pt creates bimetallic active sites with properties different from those of its components, behaving as a true bimetallic catalyst. [Copyright &y& Elsevier]

Abstract: Unsupported Pt black reduced by hydrazine looked like an agglomeration of elongated Pt particles, as confirmed by electron microscopy. Cyclic voltammetry indicated the presence of low Miller-index (e.g. {100} and {111} facets) as well as terrace structures. This Pt catalyst was subjected to deactivating treatments with hexane (nH) alone and in the presence of H2 of various pressures in two sets of experiments, both carried out at 483 and 603K. One series monitored catalytic reactions during deactivation and in subsequent standard test runs. The other series applied deactivating treatments quasi in situ in the electron spectrometer and were followed by XPS and UPS studies. More hydrogen favored the formation of C6 saturated products: isomers and methylcyclopentane (MCP). XPS detected more carbon deposited in the absence of hydrogen, and accordingly the residual activity was much less after these pretreatments, being about twice as high when the pretreatment was carried out at 483K as opposed to 603K. With the same p(H2) present in the carbonizing mixture, less C remained at 483K. The amount of retained carbon increased up to 36%. Its amount showed correlation with the activities measured in standard test runs after deactivating exposures. An abrupt increase of the activity loss appeared upon exposures at higher temperatures and with less hydrogen, resulting in 22–30%C. This was concomitant with the change of the chemical state of C: with more C, more “graphite-like” carbon and C x H y polymers. “Disordered C” or “Pt-C” entities, poisoning active Pt ensembles may have been responsible for selectivity shift. Multilayer deposits may have appeared with more than 30%C, causing severe activity loss. Deactivation by carbon must have geometric rather than electronic reasons. [Copyright &y& Elsevier]

There are over 650 million people in Africa who have no access to electricity; this is in sharp contrast to the continent's vast untapped renewable energy potential and due largely to the historical lack of investments in energy infrastructure. New investments in decentralised power generation within Sub-Saharan Africa play a progressively important role in increasing energy access and addressing the continent's electricity supply shortages. Tracking the performance of Sub-Saharan African countries along various socio-political and economic axes can spur the mobilisation of private, public and international sectors in investing in decentralised energy technologies. An increasing amount of high-resolution global spatial data are available, and used for various assessments. However, key multidimensional indicators are mainly still provided only at the national level. To this end, we present a comprehensive and consistent analysis of the attractiveness for decentralised photovoltaic technologies at an unprecedented level of detail using both high-resolution spatial data and national reports. We develop and build a new composite indicator that considers the interplay between social, political, environmental and financial factors at a granular regional level for Sub-Saharan Africa and embeds within it the importance of the local production costs at high-spatial resolution. • Composite indicator for directing/informing decentralised renewable energy investment in Sub-Saharan Africa. • Integrates technological, environmental, social, political and financial factors for decision support. • Combines country level data with high-spatial resolution (i.e. electricity production costs). • Raw data provision enabling stakeholders to focus on specific country attributes. • Interactive tool will enable users to weight indicators to their specifications. [ABSTRACT FROM AUTHOR]

An abstract of the article "Enlarged fetal iliac angle as an ultrasound marker for trisomy 21, 18 and 13 during the second trimester of pregnancy," by B. Z. Belics and colleagues, is presented.